php工厂模式实例代码

<?php 
//运算符抽象类 
abstract class Operation{ 
    private $num1=0; 
    private $num2=0; 
    public function __get($name){ 
        if(isset($this->$name)){ 
            return $this->$name; 
        } 
        return null; 
    } 
    public function __set($name,$value){ 
        $this->$name=$value; 
    } 
    abstract function getResult(); 
} 
 
//加法 
class Add extends Operation{ 
    public function getResult(){ 
        return $this->num1+$this->num2; 
    } 
} 

//减法 
class Sub extends Operation{ 
    public function getResult(){ 
        return $this->num1-$this->num2; 
    }
} 
 
//乘法 
class Mul extends Operation{ 
    public function getResult(){ 
        return $thi->num1*$this->num2; 
    } 
} 
 
//除法 
class Div extends Operation{ 
    public function getResult(){ 
        if($this->num2==0){ 
            echo "除数不能为零"; 
            return false; 
        } 
        return $this->num1/$this->num2; 
    } 
} 
 
//运算符操作工厂，来决定初始化哪个类 
class OperationFactory{ 
    static function createOperation($operate){ 
        switch($operate){ 
            case "+": 
                $oper=new Add(); 
                break; 
            case "-": 
                $oper=new Sub(); 
                break; 
            case "*": 
                $oper=new Mul(); 
                break; 
            case "/": 
                $oper=new Div(); 
        } 
        return $oper; 
    } 
} 
 
//开始测试 
$oper=OperationFactory::createOperation("+"); 
$oper->num1=3; 
$oper->num2=6; 
$result=$oper->getResult(); 
echo $result; 
?>